Make request validation shorter on domain create

app/controllers/epp_controller.rb

@@ -75,32 +75,9 @@ class EppController < ApplicationController
     epp_errors.empty?
   end
 
-  def mutually_exclusive(*selectors)
-    present_count = 0
-    selectors.each do |selector|
-      full_selector = [@prefix, selector].join(' ')
-      el = params[:parsed_frame].css(full_selector).first
-      present_count += 1 if el && el.text.present?
-    end
-
-    return if present_count <= 1
-
-    epp_errors << {
-      code: '2306',
-      msg: I18n.t(:are_mutally_exclusive, params: selectors.join(', '))
-    }
-  end
-
   # let's follow grape's validations: https://github.com/intridea/grape/#parameter-validation-and-coercion
   def exactly_one_of(*selectors)
-    present_count = 0
-    selectors.each do |selector|
-      full_selector = [@prefix, selector].join(' ')
-      el = params[:parsed_frame].css(full_selector).first
-      present_count += 1 if el && el.text.present?
-    end
-
-    return if present_count == 1
+    return if element_count(*selectors) == 1
 
     epp_errors << {
       code: '2306',
@@ -108,6 +85,14 @@ class EppController < ApplicationController
     }
   end
 
+  def mutually_exclusive(*selectors)
+    return if element_count(*selectors) <= 1
+    epp_errors << {
+      code: '2306',
+      msg: I18n.t(:mutally_exclusive_params, params: selectors.join(', '))
+    }
+  end
+
   def optional(selector, *validations)
     full_selector = [@prefix, selector].join(' ')
     el = params[:parsed_frame].css(full_selector).first
@@ -121,6 +106,16 @@ class EppController < ApplicationController
     end
   end
 
+  def element_count(*selectors)
+    present_count = 0
+    selectors.each do |selector|
+      full_selector = [@prefix, selector].join(' ')
+      el = params[:parsed_frame].css(full_selector).first
+      present_count += 1 if el && el.text.present?
+    end
+    present_count
+  end
+
   def xml_attrs_present?(ph, attributes) # TODO: THIS IS DEPRECATED AND WILL BE REMOVED IN FUTURE
     attributes.each do |x|
       epp_errors << {